Cardi B had just stepped offstage after performing for thousands in Central Park when a loud pop pierced the air, sounding like a gunshot and igniting fears of a shooting. Backstage, police commanders scrambled to find out what was going on, and quickly determined no shots had been fired. They rushed to the stage to tell the crowd.

“Remain calm,” Assistant Chief Kathleen O’Reilly pleaded into a microphone, saying the sound had been a fence falling over.

But it was too late. Frantic concertgoers ducked and rushed for a limited number of exits. Some people screamed “Shooter!” Barriers and tall fences were toppled. People fell and were trampled. Many fled shoeless. Some police officers even contributed to the pandemonium, telling people to duck and run.

Though no one was seriously injured, the chaos at the Global Citizen Festival on Saturday jolted law enforcement authorities, security experts and policymakers. It has forced an examination of whether the police need new ways of curbing the risk of crowd panic in an era when mass killings have heightened public fear of attacks.

Once the false reports of a shooting spread, controlling the crowd “was like putting toothpaste back in the tube,” Chief James R. Waters, the police counterterrorism commander, who had been on the stage, said in an interview this week.

The events in Central Park unfolded nearly a year to the day after a gunman killed 58 people at an outdoor country music concert in Las Vegas, the worst shooting in modern American history, and one in a series of mass killings at churches, concerts, newsrooms, nightclubs and schools.

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Dozens of concertgoers suffered minor injuries in the onrush of people after popping sounds triggered a scare.CreditEvan Agostini/Invision, via Associated Press

“People subjectively feel like they are in greater danger than ever before,” said Steven Adelman, the vice president of the Event Safety Alliance, a nonprofit trade association.

Police officials have defended their handling of the panic in Central Park, saying the 100 officers at the concert were able to restore order within a few minutes, in part because the department has studied shooting attacks and conducted drills.

But behind the scenes, officials are grappling with what went wrong and are adopting changes that would make events like the annual music festival safer for participants during an emergency.

Those changes include marking the entrances and exits with color-coded lights, installing runway lighting to highlight emergency routes, displaying urgent messages on screens and placing specialized teams of officers in positions high enough for them to oversee the crowd, Chief O’Reilly said on Tuesday.

“Situational awareness will be what we are messaging out next year,” Chief O’Reilly said. “People have to understand where they are.”

The police commissioner, James P. O’Neill, said on Wednesday that the police could have moved faster to get a message out to calm the crowd — not just from the stage, but on social media as well. “I think our first hit on social media was about 12 minutes into it,” he said. “We can do better there.”

Mr. O’Neill said the department would “go back and take a look at what happened and see how we can prevent it in the future.”